Pressure ulcers or bed sores are chronic wounds usually caused by a combination of increased pressure on the affected area and decreased angiogenic response. Pressure ulcers affect almost 10% of people in hospitals, with older people being at highest risk. Various techniques have been employed over the years to prevent and suppress skin breakdown incident to ulcers and bed sores. These techniques include the application of low intensity ultrasound and/or ultraviolet light to the affected area, the use of pressure-relieving mattresses and devices for rotating a patient in his/her bed to minimize localized pressure buildup on the patient's skin which is a prelude to pressure ulcers.
Although these conventional treatment protocols are satisfactory in many respects, they do involve considerable expense. Therefore, they are usually carried out only in hospitals and chronic care facilities.